JPS61113328A - Optical corresponding device between mobile bodies - Google Patents

Abstract

PURPOSE:To attain sure transmission of a voice signal with excellent privacy call without radio interference by retransmitting an optical signal when an optical axis deviation detecting means detects deviation of the optical axis at optical transmission in communicating mobile bodies with the optical signal. CONSTITUTION:In transmitting voice information from a car body CT1 to a car body CR1, a specific ID code IDR decided to the car body CR1 is set by the car body CT1 and the IDR is irradiated toward the car body CR1 through optical transmission. After the reception of the IDR, the CR1 superimposes the IDR on a focus beam O2 to irradiate the IDR of the CR1. The car body CT1 receives the focus beam O2, and when the code IDR is coincident with the irradiated code IDR before and the optical axes are coincident while the detected level is a prescribed value or over, the voice signal is converted to the transmission optical beam O1 and transmitted momentarily while being subject to time compression. When the CR1 receives the compressed voice signal, the time axis is expanded as it is. When the CT1 cannot receive the IDR, it is discriminated as the deviation of optical axes and the IDR is transmitted again. Since the information is transmitted by compressed voice, the correspondence is not disturbed even if temporary interruption of the optical axis deviation takes place because of ups/downs of a road.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical communication device between moving bodies using optical communication, which enables voice communication between moving bodies while moving, for example.

[Prior Art] Conventionally, radio waves have generally been used for communication between moving vehicles.

[Problems to be Solved by the Invention] However, it is well known that communication means using radio waves may be regulated by the Radio Law, and that there are problems such as radio interference and interference. Additionally, there is a risk that the contents of the communication may be intercepted by others, and there is a problem with confidentiality.

Such problems can be solved by optical communication. However, when performing optical communication, it is difficult to align the optical axes between vehicles for a long time due to road irregularities, vehicle vibrations, etc., and this has not been put to practical use.

In consideration of the above facts, the present invention is not subject to the regulations of the Radio Law, solves the problems of radio interference and interference, has excellent privacy, and is capable of reliably transmitting audio signals. It provides equipment.

[Means and effects for solving the problem] In the optical communication device between moving bodies according to the present invention, communication between the moving bodies is carried out by a compressed transmission method using optical communication. A mobile object receives a aiming beam emitted from one mobile object to another mobile object, determines whether communication is possible based on this aiming beam, and when communication is possible, optically transmits the audio signal in a time-compressed state. Information is exchanged between them.

Specifically, each vehicle has a unique identification code (ID code), and this ID code is sent and received between vehicles to identify the other party, and after the ID codes match, the content of the communication is transmitted from one vehicle to the other vehicle. It compresses and transmits data through modulation, allowing information to be exchanged instantaneously.

During optical transmission, the optical axis deviation detection means checks for optical axis deviation, and if optical axis deviation is detected, retransmission is performed.

[Embodiment] Fig. 1 shows an example in which the device of the present invention is installed in a car and is applied to a case where the car can communicate with each other while the car is running.

FIG. 2 shows a case in which the system is applied to a vehicle in which communication is performed between three or more vehicles by using an intermediate vehicle as an optical repeater to enable communication between the front and rear vehicles.

As described above, when communicating between vehicles by optical communication, it is quite difficult to match the optical communication paths between the vehicles while the vehicles are running due to unevenness of the road, vibration of the vehicle, and the like. Therefore, in the present invention, even if there are these disturbances while driving,
In order to enable communication, it is devised to detect instantaneous coincidence of optical communication paths (optical axes) and to compress and transmit the communication content.

An outline of communication in the apparatus of the present invention will be explained with reference to FIG. First, when transmitting audio information from the vehicle CTI to the cptx, the vehicle CTI side sets a specific predetermined ID code IDR in the vehicle CR, and this code IDR
is fired toward the vehicle CRI by optical transmission. Vehicle C
On the pl side, after receiving the code IDR, the ID code IDR of the vehicle CR1 side is emitted from the CRI side toward the CTI on the aiming beam 02.

The vehicle CTl receives this aiming beam 02, and the emitted code ID matches the previously emitted code ID,
When the light receiving level is high, that is, when the light receiving sensitivity is the best (when the optical axes match), the audio signal is instantaneously transmitted from the vehicle C1 side as the transmission light beam 01.

This instantaneous transmission is intended to prevent audio signals from being disrupted due to optical axis misalignment between transmitting and receiving light, and from mixing in external noise, thereby obtaining clear audio input. Communication is performed in the same manner when audio information is transmitted from the vehicle CRI side to the CA side.

FIG. 3 is a block diagram showing an example of an optical communication device according to the present invention, and an example of the communication operation will be explained in detail with reference to the time charts of FIGS. 4 and 5.

The optical communication device shown in FIG. 3 is an optical communication device mounted on both vehicles CT1 and CR□, and for convenience of explanation, the same drawing will be used depending on the communication state.

First, enter multiple ID needs predetermined for each vehicle into the code input switch 1l-T (here, T is vehicle C).
This means that it is installed in the optical communication equipment installed on the TI side. same as below.

(However, this T is omitted in the drawing), these are converted into 8-bit signals by the encoder 12-T, and then
The data is stored at the specified address in the memory 13-T.

Data is stored using clock signal generator 1 for ID code.
This is done based on the 6-T write clock.

17 is a reference clock oscillator.

Now, when audio is to be transmitted from the vehicle CRT to the CRI, the front/rear selector switch 7 is switched to the front CF) side at point t1 in FIG. As a result, the front (F) light emission drive circuit 8F-T enters the operating state as described later.

Next, operate the selection switch 10-T to specify the address in the memory 13-T, and read out the stored code IDR for the specific vehicle, in this example, the vehicle CR□, from the clock signal generation circuit 16-T. is read out based on
It is temporarily stored in temporary memories 15-T and 14-T.

The temporary memory 15-T is used when transmitting the code ID for the first time, and the other temporary memory 14-T is used when transmitting the code ID.
, used when retransmitting.

When the selection switch 10-T is not operated, the code ID of own vehicle 0-1 is read from the memory 13, and is used to determine whether the code matches when received from another vehicle CFtt, as will be described later.

At time t2 after the data has been stored in the temporary memories 14-T and 15-T, a display lamp (not shown) for displaying the state in which voice input is possible is turned on for a predetermined period (from t2 to t2 in the figure).
t3) lights up (Fig. 4B), [Thus, after time t2, the audio Sc input to the microphone L-T (Fig. 4C) is amplified by the amplifier 2-T, and this audio signal is It is digitally converted by the D converter 3-T. A/D conversion is performed using the sampling clock Sd (fourth clock) obtained by the frequency divider 20-T based on the reference clock from the oscillator 17-T.
(D) and the conversion operation for encoding (8 bits) is performed based on the reference clock St.

In this example, 8 KHz is used as the sampling clock Sd for A/D conversion to 8-bit data. The digital audio signal is written into the memory 4-T based on the write clock Se (FIG. 4E) from the clock generator 18-T used during data transmission.

When data writing is completed at time t3, the display lamp goes out, and the ID code read enable signal Sf (FIG. 4F) is output from the clock generator 18-T and the oscillator 17.
- Based on the reference signal from the divider 20-T, the clock signal So from the divider 20-T or Kinuta is supplied to the temporary memory 5-T. ' It is supplied to the drive circuit 8F-T via the eaves T. As a result, the light emitting element 9F provided on the front side of the vehicle CTI
-T, modulated code IDR data (serial code data) is emitted as an optical code toward the rear of the vehicle Cρl.

The branch 6-T is for switching to transmit audio data and code data to the front side or the rear side. On the other hand, a rear light receiving element 30R-R (R indicates that an optical communication device for the vehicle CFti is provided) is provided at the rear of the vehicle CR1.

The same applies hereafter), the code ID is received and converted into an electrical signal, and this is amplified by the light receiving amplifier 29R-R and supplied to the 1 combiner 28-R, after which the straight tube parallel converter 21
-R converts the code ID into parallel data. This serial/parallel conversion is performed based on a synchronization pulse synchronized with the input code IDR outputted from the synchronization pulse generator 24-R.

The parallel-converted input code ID is supplied to the coincidence detection circuit 22-H together with the own vehicle code ID 1 output from the memory 13-R, and the coincidence detection of the code data is performed. In this example, both codes are When they match, H level detection data is obtained.

The output of the combiner 28-R is further transmitted to the received light level detector 23.
-R and when the received input code IDE is at a predetermined level (receivable level) or higher, H level discrimination data is obtained.

This discrimination data and detection data are the first AND gate 2.
As described above, when the input code IDR matches the code ID value of the own vehicle CRI and is above the receivable level, the output of the first ant game) 26-H becomes H.
become the level.

Time point 14 (first AND gate 26-R at H→ in FIG. 4)
When the output Si (I in the same figure) is obtained, the read clock obtained from the external circuit 20-R based on the reference signal generated by the oscillator 17-R is temporarily supplied to the memory 14-T and stored therein. The code ID for own vehicle CRt is read out and supplied to the turnout 6-H.
A signal indicating that light is received on the rear side with the code "ID" is supplied from the combiner 2B-R to the switch 6-R, which selects the splitter 6-R for the rear side and transmits the signal to the rear light emitting drive circuit 8R. -R operates and rear light emitting element 9R-R
is excited. This causes the aiming beam 02 to be aligned with the vehicle C.
Fired towards TI.

Since the aiming beam 02 is received by the light receiving element 30F-T provided on the front side of the vehicle CA, the aiming beam 02 is
As in the case of +, the other party code IDR included in this aiming beam 02 is supplied to the code coincidence detection circuit 22-T and the received light level detection circuit 23-T, respectively, and the optical axis of the vehicle cT□ and the vehicle C=1 is When the output Sg (FIG. 4G) from the first AND gate 26-R is obtained at the matching time tga, the code I from the temporary memory 15-T is
The reading of D is stopped.

The first AND output Sg is also supplied to the clock generator 18-T, whereby the read clock Sn of FIG. 5N is supplied from the clock generator 18-T to the memory 4-T.

The frequency of the read reflex clock Sn is m of the write clock Se.
Therefore, the time axis during reading is compressed to l/m of the time axis during writing. The compressed parallel audio data is converted into serial data by a parallel/serial conversion circuit 5-T. FIG.
-Supplied from T (synchronized with read clock Sn)
A clock SO is shown, and the period α in FIG. 1 shows one block data group that has been parallel-to-serial converted.

The compressed audio data is supplied to the branching device 6-T, the front light emitting drive circuit 8F-T, and then to the front light emitting element 9F-T, where it is converted into an optical signal, which becomes a transmitted light beam 0□ and is emitted to the vehicle CRI side. be done. When the reading of the audio signal ends at time tga, the end bit is read from the temporary memory 39-T until time t7a by the clock bit signal from the branch circuit 20-T, and the beam o is
1 and is fired toward the vehicle CRI side.

The transmission period (transmission period) including compressed audio data is an extremely short period up to time tga-tea.

On the other vehicle CRt side, the transmitted light beam 01 is sent to the rear light receiving element 3.
The light is received by 0R-R, amplified by the rear light-receiving amplifier 29-R, and supplied to the serial/parallel converter 31-H via the synthesizer 28-R, where it is converted into parallel audio data while keeping the time axis compressed state. be done. The stand parallel conversion is performed using a serial/parallel conversion clock Sp (FIG. 5P) obtained by frequency-dividing the synchronization pulse from the synchronization pulse generation circuit 24-R by the frequency divider 20-R.

This parallel audio data is stored in memory 32-R.

The store write clock Sq (Q in the figure) is generated by the clock generator 19-R used when receiving data based on the synchronization pulse from the synchronization pulse generation circuit 24-R.

The writing of data is completed at times t and b, and then the clock signal generated by the end bit synchronization signal generation circuit 24-R is transmitted, and the signal is serial-parallel converted by the S/P conversion circuit 21-R. The end bit code output from the temporary memory 39-R is detected by the end bit coincidence detection circuit 3.
8-R respectively. If they match, the IDR code reverse transmission is ended by transmitting an ID code reverse transmission end signal Sj (FIG. 4 J) to the temporary storage circuit 14-H. The reverse code transmission to vehicle GT1 is stopped.

At the same time, the read clock Sk from the clock generator 19-R is generated based on the reference signal generated by the oscillator 17-R.
(K in FIG. 4), the time-axis compressed audio data is read out from the memory 32-R' after being time-axis expanded by m times.

This audio data is supplied to the switch 33-R. The switching circuit 33 supplies audio data to the D/A converter 34 or
This is for selecting whether to supply the signal to the parallel/serial converter 5-T, and as will be described later, all signals are supplied to the D/A converter 34 when not used as an optical repeater. That is, the first AND output gate 26-R (corresponding to Si) is at H level, and the second AND gate (detected data inverted by the inverter 25-R and 1 discrimination data are supplied). ) When the second AND output obtained from 27-R is at L level, the audio data read out by memory 32-R is selected and supplied to D/A converter 34-R, where it is D/A converted. Ru.

In addition, during this D/A conversion process, a latch pulse S is used to latch and analogize audio data every 8 bits from the frequency divider 20-R based on the reference signal generated by the oscillator 17-R. Figure 4L) is output.

The analog audio signal Sm (M in FIG. 4) is emitted from the speaker 36-R via the amplifier 35-R during a period from time tea to t@ (corresponding to time t2 to t3).

Next, when transmitting audio signals, the transmission between vehicle CTI and vehicle 0 section 1 is
Retransmission when optical axis misalignment occurs between received lights will be explained.

When transmitting audio signals from vehicle T1 to vehicle CRt, vehicle CR
+ is the IDR for aiming beam 02 until the detection time tya (tyJ) of the end bit of the end of the audio signal from the vehicle CTI.
transmitting code. Therefore, by detecting the coincidence of the IDR code for the aiming beam 02 and the detection of the light reception level on the vehicle CRT side as described above, the ant game ) 26-T is at L level when the optical axis is misaligned (t□a-tua), as shown in FIG. 6T. On the other hand, during audio signal transmission, the H level output Sma output from the clock generator 1B-T and the inverted signal Su of the SA via the inverter 40-T are input to the AND gate 41-T. Since the output Sw of 41-T becomes the optical axis deviation detection signal Sw during audio signal transmission, this signal is sent to the OR gate 42-
By supplying a temporary memory, 15-T, through T,
,′.

Then, retransmission can be performed in the same manner as after the ID code transmission start signal Sf.

To summarize the above communication operation, it is as follows, (
It is.

■ Deliver the other party's code ID to the other party's vehicle CR1.

sending out.

■ The other party's vehicle CR1 determines the IDR, and when it matches the own vehicle code IDFII, sends the own vehicle code ID large to the vehicle CTI.

■ Upon receiving the aiming beam 02 at this time, code matching is detected and received light level is detected.

(2) When each of the conditions in (2) is satisfied, the compressed audio data is transmitted, and if a deviation of the optical axis is detected during the transmission, the process returns to (2).

- The other party's vehicle CRI stores this compressed audio data in memory and expands the time axis to its original state.

When the received light level is high and the ID needs match again, the time axis expanded audio data is D/A converted and the speaker is driven.

■ Recognize the contents of the message sent from the other party's vehicle CTI by ■ If you reverse the operations from ■ to ■, CRI→CA.

It is possible to communicate with.

Note that all control of these communication states is processed based on a control program written in the ROM of the microcomputer 43.

Further, the retransmission may be such that only the remaining information after the optical axis shift is detected is transmitted.

Next, as shown in FIG. 2, a case will be described in which communication between vehicles Cr2 and CR2 is performed by using intermediate vehicle Cr+2 as an optical repeater.

In this case, similarly to the case of voice information exchange between vehicles CA1 and Cζ1, the predetermined identification code ID for vehicle-CF2 transmitted from vehicle CFQ2 to 0M2, and vehicle C
Coincidence with the discrimination code IDM of r52 is detected, and the level of received light is also detected.

At this time, since the 1 discrimination code ID and IDn do not match, when the light reception level is high,
27-M output is It becomes H level.

As a result, the write clock from the clock generator 16-M is supplied to the memory 13-M. At this time, the code ID is supplied to the serial/parallel converter 37 via the light receiving element 30R-M and the combiner 28-M, so that F is stored in the memory 13-M from the parallel-converted code.

Next, based on the read clock from the clock generator 16-M, the code ID is set to the temporary memory 14-M, 15-M.
[The code ID is stored and read out continuously from the temporary memory 14-M by the clock from the frequency divider 20-M, and then sent to the rear light receiving element 9R- through the same signal path as described above.
Code ID from M becomes a aiming beam and is fired toward vehicle cR2.

Then, in the same manner as in the case of FIG. 1, the compressed audio data from the vehicle CR2 is temporarily stored in the memory 32-M, and this compressed audio data is passed through the switching circuit 33-M and the parallel/serial conversion circuit 5-M. By being supplied to the generating element 9F-M, the compressed audio data is optically transmitted to the vehicle CF2 side.

The optical axis deviation is between vehicles CR2 and Cr+2 and between 0M2 and C
The optical axis deviations checked in the same way as above are detected between F2, and retransmission is performed if necessary.

[Effects of the Invention 1] Since the present invention is configured as described above, it has the following features compared to the prior art.

■ Since it is optical communication, it is not subject to regulations under the Radio Law.

■ Compared to radio wave communication, the communication range is extremely narrow, so communication performance is less likely to deteriorate due to external factors such as radio interference and interference.

■ Since the optical communication path is localized, communication is extremely secure. In particular, if a discrimination code is used, there is no risk that the communication contents will be inadvertently intercepted even if an unrelated vehicle traveling on the same route gets between the communication channels.

■ Compressed voice data is optically communicated only when the optical axes of the communication vehicles match, so even if the communication path is temporarily interrupted by road irregularities, it does not interfere with communication, and it does not introduce external noise.

- Since the optical axis is detected based on the optical axis of the other party, communication can be performed when the received light levels of both parties are stable.

■ It is possible to communicate with a mobile object several times before or several times after.

(2) During optical transmission, the optical axis deviation detection means checks for optical axis deviation, and if optical axis deviation is detected, retransmission is performed, so audio data can be sent reliably.

Moreover, since it is compressed transmission, it can be retransmitted in a short time.

[Brief explanation of the drawing]

1 and 2 are diagrams showing communication states between moving vehicles to which an optical communication device according to an embodiment of the present invention is applied, and FIG. 3 is a diagram showing an example of an optical communication device between moving bodies according to the present invention. The block diagrams and FIGS. 4 to 6 are timing charts for explaining the operation, respectively. 1...Microphone, 4.13~15.32.39...Memory, 9F, 9R
---Light emitting element, 16.18.19...Clock generator, 20φ fist frequency divider, 22/11 match code match detection circuit, 23/9 match reception level detection circuit. 30F, 30R... Light receiving element, 36... Speaker, 38... End bit coincidence detection circuit.

Claims (2)

[Claims] (1) Receive the aiming beam irradiated from one moving object to the other moving object, determine whether communication is possible based on this aiming beam, and when communication is possible, optically transmit the audio signal with time axis compression. An optical communication device between moving bodies that exchanges information between moving bodies by An optical communication device between mobile bodies characterized by performing retransmission in some cases. (2) An optical communication device between moving bodies according to claim 1, wherein an optical communication device of a moving body interposed between several units before or after several units that exchange information is used as an optical repeater.